scholarly journals Observation of Ionization of Laser Excited Atoms by Synchrotron Radiation

1984 ◽  
Vol 86 ◽  
pp. 128-131
Author(s):  
J.M. Bizau ◽  
F. Wuilleumier ◽  
P. Gerard ◽  
P. Dhez ◽  
B. Carré ◽  
...  
Keyword(s):  
Synchrotron Radiation ◽  
Photoelectron Spectroscopy ◽  
Oscillator Strengths ◽  
Final States ◽  
Initial State ◽  
Final State ◽  
Core Electron ◽  
Output Mirror ◽  
Initial States ◽  
A New Technique

We have begun a program to measure oscillator strengths of autoionizing resonances that result from a transition in the VUV between a laser excited initial state and a final state in which a core electron is promoted. These measurements demonstrate a new technique to combine synchrotron radiation, laser pumping, and photoelectron spectroscopy.Measurements of the energy positions of autoionizing resonances have been honed to a fine art over the past 50 years. Total cross section measurements and the parameters that describe autoionizing resonances have been determined. Most of these studies have been made from the dipole allowed ground state. Recently autoionizing resonances have been observed from excited initial states and from ion initial states. We have heard several talks, at this meeting which described some of this type of research. In the measurements to be described in this paper, laser radiation is combined with synchrotron radiation, as shown schematicaly in Figure 1, to study the photoionization from excited initial states to continuum final states or to autoionizing final states. Continuum radiation from the Aneau de Collisions d’Orsay (ACO), which is installed at the Universite de Paris-Sud, in Orsay France, is monochromatized by a toroidal grating monochromator (TGM) and is focused by a toroidal output mirror on to a weakly collimated sodium beam emanating from a furnace mounted on the axis of a cylinderical mirror analyzer (CMA). This electron spectrometer is used to study the kinetic energy distribution of the ejected photoelectrons produced by the interaction of the photon beam with the focused synchrotron radiation.

scholarly journals Photoionization Dynamics of Small Molecules With Synchrotron Radiation: State Preparation by Pepico and Tpepico

1991 ◽  
Vol 11 (3-4) ◽  
pp. 131-142 ◽  
Author(s):  
Paul Marie Guyon
Keyword(s):  
Synchrotron Radiation ◽  
Small Molecules ◽  
Internal Energy ◽  
Photoelectron Spectroscopy ◽  
Time Of Flight ◽  
Initial State ◽  
Final State ◽  
State Preparation ◽  
Synchroton Radiation

The use of synchroton radiation combined with TPEPICO experiments to study the photoionization dynamics of molecules at Orsay's synchroton radiation facility is discussed. The initial state preparation by Threshold Photoelectron Spectroscopy and final state-mass and internal energy spectroscopy by time of flight analysis of photoelectrons as well as ions in coincidence with threshold electrons is illustrated by the TPES of HCl, the TOF TPES of O2 and the TPEPICO spectra of NO+ fragments from the decay of state selected N2O+ ions.

scholarly journals Patterns and paschen-back analogue in the stark-effect for neon

1929 ◽  
Vol 123 (791) ◽  
pp. 80-103 ◽  
Keyword(s):  
Quantum Number ◽  
Stark Effect ◽  
Selection Rule ◽  
Theoretical Calculations ◽  
Zeeman Effect ◽  
Final States ◽  
Outer Electron ◽  
Initial State ◽  
Final State ◽  
Left Handed

While the Stark-effect has not been studied so extensively as the Zeeman-effect, either in the experiments or in their interpretations, many of the more prominent features have been observed and have received adequate explanation on the quantum theory. Among these may be mentioned the patterns characteristic of the different series in the singlet system of parhelium. The variety of observed patterns in the Stark-effect, as contrasted with the normal Zeeman-effect found for all series of this system, arises from a differential action of the external electric field on the initial and final states, and a breaking down of the usual selection rule for the azimuthal quantum number. Some simplification is brought about, however, by the fact that only the absolute value of the quantum number m has any meaning in the interpretation of these photographs, since the action of the field is the same for right or left-handed motion of the outer electron in its orbit. This results in asymmetrical patterns for all the lines. The number of components observed in the patterns of individual lines of parhelium is in accord with the theoretical view that the vector j (here equal to l ) is resolved along the direction of the applied field to give the integral m values ranging from - j to + j , and that the usual selection rule holds for m . The displacements and intensities are in excellent agreement with the theoretical calculations based on the perturbation theory of quantum mechanics. The spacing of the sub-levels identified by ± m in the initial state is decidedly irregular in the Stark-effect as compared with the normal Zeeman-effect, where the displacements are proportional to m . The Zeeman order of the levels is usually reversed, in fact, and the spacing is uneven. Displacements in the final state are theoretically very small, and have not been observed with certainty. In the Stark-effect for orthohelium (triplet system) the same group of patterns was observed. An explanation of these observations, which is slightly less satisfactory than that obtained with parhelium, has been made by similar methods, neglecting the electron spin. Thus the m values were again given ranges determined in each case by the l of the outer electron, and not by the j for the whole atom. Most of the plates failed to reveal any of the fine structure of the normal orthohelium spectrum.

scholarly journals EIGENMODE OF THE DECISION-BY-MAJORITY PROCESS IN COMPLEX NETWORKS

2008 ◽  
Vol 11 (04) ◽  
pp. 565-579
Author(s):  
MAKOTO UCHIDA ◽  
SUSUMU SHIRAYAMA
Keyword(s):  
Complex Networks ◽  
Network Models ◽  
Ising Models ◽  
Final States ◽  
Zero Temperature ◽  
Opinion Formation ◽  
Initial State ◽  
Final State ◽  
Numerical Studies ◽  
Eigenmode Analysis

The nature of the dynamics of opinion formation or zero-temperature Ising models modeled as a decision-by-majority process in complex networks is investigated using eigenmode analysis. The Hamiltonian of the system is defined and estimated by eigenvectors of the adjacency matrix constructed from several network models. The rule of the process is assumed to be equivalent to the minimization of the Hamiltonian. The initial and final states of the dynamics are decomposed on the basis of the eigenvectors. The process and the eigenmodes are analyzed by numerical studies. We show that the magnitude of the coefficient for the largest eigenvector at the initial states is the key determinant for the resulting dynamics. We thus prove that the final state of the dynamics can be estimated by the eigenmodes of the initial state.

scholarly journals Transverse Single Spin Asymmetries of Forward π0 and Jet-like Events in s = 500 GeV Polarized Proton Collisions at STAR

2016 ◽  
Vol 40 ◽  
pp. 1660037 ◽  
Author(s):  
Yuxi Pan
Keyword(s):  
Final States ◽  
High Transverse Momentum ◽  
Initial State ◽  
Final State ◽  
Spin Asymmetries ◽  
Proton Collisions ◽  
Single Spin ◽  
Single Spin Asymmetries ◽  
Polarized Proton ◽  
State Models

The large transverse single spin asymmetries (SSA) of high [Formula: see text] inclusive hadrons produced in polarized proton collisions are usually explained by means of collinear twist-3 multi-parton correlations. In this picture these asymmetries can originate from initial-state twist-3 parton distributions in the polarized proton and/or through the coupling between proton transversity and twist-3 fragmentation functions. The measurement of SSA for forward inclusive hadrons produced in [Formula: see text] collisions out to high transverse momentum helps to examine the validity and interplay of these initial- and final-state models. These models can be further explored by investigating the dependence of the SSA on event topologies. We present our latest status on the measurement of SSA for forward inclusive [Formula: see text] detected within [Formula: see text] in [Formula: see text] = 500 GeV [Formula: see text] collisions as well as its dependence on event topologies. We will also present our analysis of Sivers and Collins asymmetries for forward jet-like events consisting of multi-photon final states. The measurements are based on the data taken in 2011 with integrated luminosity [Formula: see text] 22 [Formula: see text].

scholarly journals QUIESCENT COSMOLOGY AND THE FINAL STATE OF THE UNIVERSE

2008 ◽  
Vol 17 (03n04) ◽  
pp. 571-576 ◽  
Author(s):  
PHILIPP A. HÖHN ◽  
SUSAN M. SCOTT
Keyword(s):  
Mathematical Formulation ◽  
Primary Objective ◽  
Mathematical Framework ◽  
Final States ◽  
Structure And Properties ◽  
Initial State ◽  
Final State ◽  
Future Singularity ◽  
Definition Of ◽  
The Universe

It has long been a primary objective of cosmology to understand the apparent isotropy in our universe and to provide a mathematical formulation for its evolution. A promising school of thought for its explanation is quiescent cosmology, which already possesses a mathematical framework, namely the definition of an isotropic singularity, but only for the initial state of the universe. A complementary framework is necessary in order to also describe possible final states of the universe. Our new definitions of an anisotropic future endless universe and an anisotropic future singularity, whose structure and properties differ significantly from those of the isotropic singularity, offer a promising realization for this framework. The combination of the three definitions together may then provides the first complete formalization of the quiescent cosmology concept.

π* ← π Shakeup Satellites for the Analysis of Structure and Bonding in Aromatic Polymers by X-Ray Photoelectron Spectroscopy

1986 ◽  
Vol 40 (2) ◽  
pp. 224-232 ◽  
Author(s):  
Joseph A. Gardella ◽  
Susan A. Ferguson ◽  
Roland L. Chin
Keyword(s):  
Quantitative Analysis ◽  
Surface Analysis ◽  
Photoelectron Spectroscopy ◽  
Polymer Surface ◽  
Surface Region ◽  
Initial State ◽  
Final State ◽  
Near Surface ◽  
Peak Fitting ◽  
Pi Orbitals

The applications of ESCA to polymer surface analysis include the use of the secondary final-state effects which lead to satellite structure near the core-level photoemission (PE) lines. Specifically, unsaturated and aromatic functionalities in organic compounds and polymers lead to π* ← π shakeup peaks of less than 10 eV lower kinetic energy (higher binding energy). In the surface analysis of polymers, these features can be utilized for qualitative analysis, identification of the presence and structure of aromatic bonding, and quantitative analysis in determining the amount of a particular block or the aromatic containing function in the near-surface region. Carbon Is shakeups are most often used, but the present study includes detailed qualitative and quantitative analysis of shakeup structures from PE lines from each type of atom in hydrocarbon-, siloxane-, and sulfur-containing polymers. These results show the importance of including the shakeup intensity in quantitative peak area calculations and in peak fitting of complex PE envelopes. These studies prove in a variety of systems that the effects of third-row atoms on the final state lead to the presence of shakeup features in atoms with orbitals which do not participate in the aromatic orbital initial state, thus complicating interpretation of structure from the presence of these features. Results from the siloxane and sulfone polymers indicate that previously held assumptions about the nature of the initial-state molecular orbital may overlook the contribution of empty 3d orbitals or increased charge density on the Si or S atom which would spread the pi orbitals to the oxygen in the aromatic siloxane or sulfone systems. Finally, analysis of these features can provide quantitative analysis of polymeric surface structure by monitoring the relative intensity of the feature to the main PE line.

Local limit theorems for non-critical Galton–Watson processes by or without immigration

1982 ◽  
Vol 19 (02) ◽  
pp. 262-271
Author(s):  
R. Höpfner
Keyword(s):  
Limit Theorems ◽  
Critical Case ◽  
Transition Probabilities ◽  
Local Limit ◽  
Limiting Distributions ◽  
Initial State ◽  
Final State ◽  
Initial States ◽  
Local Limit Theorems

From normal limiting distributions of suitably normed sequences of Galton–Watson processes or Galton-Watson processes with immigration, with initial states tending to ∞, we can derive local limit theorems for the transition probabilities Qn (i, j) and Pn (i, j) in the non-critical case, when initial state i and final state j tend to ∞ with n.

Core-Level Electron Binding Energy Change of Evaporated Pd

1985 ◽  
Vol 48 ◽  
Author(s):  
Shigemi Kohiki
Keyword(s):  
Binding Energy ◽  
Electron Binding Energy ◽  
Initial State ◽  
Final State ◽  
Core Electron ◽  
Palladium Clusters ◽  
Positive Core ◽  
The Mean ◽  
Valence Band Electron ◽  
Electron Binding

ABSTRACTPositive core-electron binding energy shifts in small palladium clusters supported on cadmium telluride substrate are shown to arise from the initial-state effects those are more sensitive to cluster size than are the final-state properties and the mean valence band electron binding energy is primarily responsible for the Pd 3d5/2 electron binding energy in lower coverage region (Pd ≲ 1×1015 atoms-cm−2).

scholarly journals A Fit to the Available e+e-→Λc+Λ-c- cross Section Data Nearby Production Threshold by Means of a Strong Correction to the Coulomb Enhancement Factor

Universe ◽  
2021 ◽  
Vol 7 (11) ◽  
pp. 436
Author(s):  
Antonio Amoroso ◽  
Stefano Bagnasco ◽  
Rinaldo Baldini Ferroli ◽  
Ilaria Balossino ◽  
Monica Bertani ◽  
...  
Keyword(s):  
Cross Section ◽  
Enhancement Factor ◽  
Final States ◽  
Cross Section Data ◽  
Initial State ◽  
Final State ◽  
Production Threshold ◽  
Section Data ◽  
State Radiation ◽  
Radiation Technique

There are two available sets of data on the e+e−→Λc+Λ¯c− cross section at energies close to the production threshold, collected by the Belle and by the BESIII Collaborations. The measurement of the former, performed by means of the initial state radiation technique, is compatible with the presence of a resonance, called ψ(4660), observed also in other final states. On the contrary, the latter is measured an almost flat and hence non-resonant cross section in the energy region just above the production threshold, but the data stop before the possible rise in the cross section for the resonant production. We propose an effective model to describe the behavior of the data near this threshold, which is based on a Coulomb-like enhancement factor due to the strong interaction among the final state particles. In the framework of this model, it is possible to describe both datasets.

Local limit theorems for non-critical Galton–Watson processes by or without immigration

1982 ◽  
Vol 19 (2) ◽  
pp. 262-271 ◽  
Author(s):  
R. Höpfner
Keyword(s):  
Limit Theorems ◽  
Critical Case ◽  
Transition Probabilities ◽  
Local Limit ◽  
Limiting Distributions ◽  
Initial State ◽  
Final State ◽  
Initial States ◽  
Local Limit Theorems

From normal limiting distributions of suitably normed sequences of Galton–Watson processes or Galton-Watson processes with immigration, with initial states tending to ∞, we can derive local limit theorems for the transition probabilities Qn (i, j) and Pn (i, j) in the non-critical case, when initial state i and final state j tend to ∞ with n.

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